Dump the Ore!

Unit Train Unloading

Dump the Ore!

Fast Unloading of Iron Ore transported by Rail
Unit trains are in common use when it comes to in-land transport of bulk solids over great distances. To keep the pace of transport, fast unloading is of paramount interest. How to afford fast unloading is described in this article.
(ed. WoMaMarcel - 27/7/2015)
<Blank Space>

Cost-effective Workhorses

A variety of systems exist for unloading iron ore shipments. By rail, cars filled with iron ore convey their loads to processing sites, directly to blast furnaces or, in the past, to ore docks to be loaded into ships. Today’s typical discharge system is the rotary railcar dumper, which turns cars over to spill their contents. Bulk ore is unloaded into pits containing conveyors, which carry the ore away to stockpiles.

Rotary car dumpers  are cost-effective workhorses that are perfect for handling iron ore. Dumping cycle times can be as fast as 35 seconds per car, and tonnage throughput can reach 5,000-plus tons per hour. The rotary dumper is the preferred choice for high speed automatic dumping of both rotary coupled cars and random car applications. Unloading rates increase dramatically when multiple dumpers are installed, in tandem, triple or even quadruple configuration.

Fastest unloading times are realized when dumper installations are matched to unit trains of iron ore. To achieve the fastest times and the highest productivity with minimal personnel, railcar dumper unloaders must be matched to support equipment such as train positioners, car indexers, traveling hammermills (when applicable, according to climate) and track systems designed to handle high numbers of railcars.

The Dumping Cycle

A dumping cycle begins when a loaded railcar moves into position and the operator initiates the unloading process. As the dumper cradle begins to rotate, clamp arms leave their support posts and the clamps descend to the top of the car. By the time rotation reaches 15 degrees, the spill truss supports the side of the car and the clamps have locked onto it. The car is securely gripped and supported throughout the rest of the rotation cycle.

Railcar dumper at work.

By the time the car has been rotated 160 degrees, dumping action has normally been completed. Barrel movement is then reversed and the car returns to its upright position. As this is happening, the clamps release, the platen locks disengage the platen, hooks align the platen rails with the yard tracks and the empty car is ready to exit the dumper. Stop, reverse and speed changes are controlled by limit switches for safe and reliable operation.

The unloaders’ manufacturer should carefully analyze each potential application to establish peak forces encountered during each phase of wagon unloading. This ensures the proper sizing of drives, arm configurations and wheel chocks. Precise engineering methodology will assure successful operations for many decades.
When circumstances call for it, railcar dumping systems can be adapted and customized beyond their standard features to match special site or environmental considerations. In this context, this means bulk handling requirements that are even more demanding than the accepted standards for trains and railcars. Since iron ore is a heavy, punishing material, it can easily fall into this category. Some operations need an unloader that is robust enough to handle iron ore.
Whether the bulk material is iron ore, coal, limestone or even wood chips, if it can be loaded into an open-top car, then a Heyl & Patterson dumper can empty it.

Most read

Upcoming Events